linux.git/drivers/md/dm.c, branch v5.12

dm: don't report "detected capacity change" on device creation

2021-03-22T16:32:32+00:00

When a DM device is first created it doesn't yet have an established
capacity, therefore the use of set_capacity_and_notify() should be
conditional given the potential for needless pr_info "detected
capacity change" noise even if capacity is 0.

One could argue that the pr_info() in set_capacity_and_notify() is
misplaced, but that position is not held uniformly.

Signed-off-by: Mikulas Patocka 
Fixes: f64d9b2eacb9 ("dm: use set_capacity_and_notify")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer

dm: fix deadlock when swapping to encrypted device

2021-02-11T14:45:28+00:00

The system would deadlock when swapping to a dm-crypt device. The reason
is that for each incoming write bio, dm-crypt allocates memory that holds
encrypted data. These excessive allocations exhaust all the memory and the
result is either deadlock or OOM trigger.

This patch limits the number of in-flight swap bios, so that the memory
consumed by dm-crypt is limited. The limit is enforced if the target set
the "limit_swap_bios" variable and if the bio has REQ_SWAP set.

Non-swap bios are not affected becuase taking the semaphore would cause
performance degradation.

This is similar to request-based drivers - they will also block when the
number of requests is over the limit.

Signed-off-by: Mikulas Patocka 
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer

dm: add support for passing through inline crypto support

2021-02-11T14:45:25+00:00

Update the device-mapper core to support exposing the inline crypto
support of the underlying device(s) through the device-mapper device.

This works by creating a "passthrough keyslot manager" for the dm
device, which declares support for encryption settings which all
underlying devices support.  When a supported setting is used, the bio
cloning code handles cloning the crypto context to the bios for all the
underlying devices.  When an unsupported setting is used, the blk-crypto
fallback is used as usual.

Crypto support on each underlying device is ignored unless the
corresponding dm target opts into exposing it.  This is needed because
for inline crypto to semantically operate on the original bio, the data
must not be transformed by the dm target.  Thus, targets like dm-linear
can expose crypto support of the underlying device, but targets like
dm-crypt can't.  (dm-crypt could use inline crypto itself, though.)

A DM device's table can only be changed if the "new" inline encryption
capabilities are a (*not* necessarily strict) superset of the "old" inline
encryption capabilities.  Attempts to make changes to the table that result
in some inline encryption capability becoming no longer supported will be
rejected.

For the sake of clarity, key eviction from underlying devices will be
handled in a future patch.

Co-developed-by: Eric Biggers 
Signed-off-by: Eric Biggers 
Signed-off-by: Satya Tangirala 
Signed-off-by: Mike Snitzer

dm table: fix DAX iterate_devices based device capability checks

2021-02-09T13:45:30+00:00

Fix dm_table_supports_dax() and invert logic of both
iterate_devices_callout_fn so that all devices' DAX capabilities are
properly checked.

Fixes: 545ed20e6df6 ("dm: add infrastructure for DAX support")
Cc: stable@vger.kernel.org
Signed-off-by: Jeffle Xu 
Signed-off-by: Mike Snitzer

dm: cleanup of front padding calculation

2021-02-03T15:10:05+00:00

Add two helper macros calculating the offset of bio in struct dm_io and
struct dm_target_io respectively.

Besides, simplify the front padding calculation in
dm_alloc_md_mempools().

Signed-off-by: Jeffle Xu 
Signed-off-by: Mike Snitzer

block: store a block_device pointer in struct bio

2021-01-25T01:17:20+00:00

Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device.  From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.

Signed-off-by: Christoph Hellwig 
Acked-by: Tejun Heo 
Signed-off-by: Jens Axboe

dm: eliminate potential source of excessive kernel log noise

2021-01-08T20:56:35+00:00

There wasn't ever a real need to log an error in the kernel log for
ioctls issued with insufficient permissions. Simply return an error
and if an admin/user is sufficiently motivated they can enable DM's
dynamic debugging to see an explanation for why the ioctls were
disallowed.

Reported-by: Nir Soffer 
Fixes: e980f62353c6 ("dm: don't allow ioctls to targets that don't map to whole devices")
Signed-off-by: Mike Snitzer

Merge tag 'for-5.11/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2020-12-22T21:27:21+00:00

Pull device mapper updates from Mike Snitzer:

 - Add DM verity support for signature verification with 2nd keyring

 - Fix DM verity to skip verity work if IO completes with error while
   system is shutting down

 - Add new DM multipath "IO affinity" path selector that maps IO
   destined to a given path to a specific CPU based on user provided
   mapping

 - Rename DM multipath path selector source files to have "dm-ps" prefix

 - Add REQ_NOWAIT support to some other simple DM targets that don't
   block in more elaborate ways waiting for IO

 - Export DM crypt's kcryptd workqueue via sysfs (WQ_SYSFS)

 - Fix error return code in DM's target_message() if empty message is
   received

 - A handful of other small cleanups

* tag 'for-5.11/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm cache: simplify the return expression of load_mapping()
  dm ebs: avoid double unlikely() notation when using IS_ERR()
  dm verity: skip verity work if I/O error when system is shutting down
  dm crypt: export sysfs of kcryptd workqueue
  dm ioctl: fix error return code in target_message
  dm crypt: Constify static crypt_iv_operations
  dm: add support for REQ_NOWAIT to various targets
  dm: rename multipath path selector source files to have "dm-ps" prefix
  dm mpath: add IO affinity path selector
  dm verity: Add support for signature verification with 2nd keyring
  dm: remove unnecessary current->bio_list check when submitting split bio

Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block

2020-12-16T20:57:51+00:00

Pull block updates from Jens Axboe:
 "Another series of killing more code than what is being added, again
  thanks to Christoph's relentless cleanups and tech debt tackling.

  This contains:

   - blk-iocost improvements (Baolin Wang)

   - part0 iostat fix (Jeffle Xu)

   - Disable iopoll for split bios (Jeffle Xu)

   - block tracepoint cleanups (Christoph Hellwig)

   - Merging of struct block_device and hd_struct (Christoph Hellwig)

   - Rework/cleanup of how block device sizes are updated (Christoph
     Hellwig)

   - Simplification of gendisk lookup and removal of block device
     aliasing (Christoph Hellwig)

   - Block device ioctl cleanups (Christoph Hellwig)

   - Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig)

   - Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig)

   - sbitmap improvements (Pavel Begunkov)

   - Hybrid polling fix (Pavel Begunkov)

   - bvec iteration improvements (Pavel Begunkov)

   - Zone revalidation fixes (Damien Le Moal)

   - blk-throttle limit fix (Yu Kuai)

   - Various little fixes"

* tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits)
  blk-mq: fix msec comment from micro to milli seconds
  blk-mq: update arg in comment of blk_mq_map_queue
  blk-mq: add helper allocating tagset->tags
  Revert "block: Fix a lockdep complaint triggered by request queue flushing"
  nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class
  blk-mq: add new API of blk_mq_hctx_set_fq_lock_class
  block: disable iopoll for split bio
  block: Improve blk_revalidate_disk_zones() checks
  sbitmap: simplify wrap check
  sbitmap: replace CAS with atomic and
  sbitmap: remove swap_lock
  sbitmap: optimise sbitmap_deferred_clear()
  blk-mq: skip hybrid polling if iopoll doesn't spin
  blk-iocost: Factor out the base vrate change into a separate function
  blk-iocost: Factor out the active iocgs' state check into a separate function
  blk-iocost: Move the usage ratio calculation to the correct place
  blk-iocost: Remove unnecessary advance declaration
  blk-iocost: Fix some typos in comments
  blktrace: fix up a kerneldoc comment
  block: remove the request_queue to argument request based tracepoints
  ...

dm: remove unnecessary current->bio_list check when submitting split bio

2020-12-04T23:04:35+00:00

The depth-first splitting is introduced in commit 18a25da84354 ("dm:
ensure bio submission follows a depth-first tree walk"), which is used
to fix the potential deadlock in case of the misordering handling of
bios caused by bio_list. There're two paths submitting split bios,
dm_wq_work() from worker thread and submit_bio() from application. Back
upon that time, dm_wq_work() thread calls __split_and_process_bio()
directly and thus will not trigger this issue since bio_list doesn't
exist here. So this issue will only be triggered from application
calling submit_bio(), and the fix has to check if current->bio_list is
non-NULL to distinguish this case.

However since commit 0c2915b8c6db1 ("dm: fix missing imposition of
queue_limits from dm_wq_work() thread"), dm_wq_work() thread calls
submit_bio_noacct() and thus also uses bio_list. Since then all entries
into __split_and_process_bio() are under protection of bio_list, and
thus the checking of current->bio_list when determinning if the
depth-first principle should be used, seems kind of nonsense. After all
the checking always succeeds now.

Fixes: 0c2915b8c6db1 ("dm: fix missing imposition of queue_limits from dm_wq_work() thread")
Signed-off-by: Jeffle Xu 
Signed-off-by: Mike Snitzer